Self-propelled screeding machine



J. H. CLARY Filed May 26, 1952 0 lo 10 a; W .1: f as :7 i 2 I 54 rfomv H C4422,

IN VEN TOR.

ATTOQNEY,

Patented Aug. 31, 1954 UNITED STATES PATENT OFFICE 2,687,679 SELF-PROPELLED SCREEDING MACHINE John H. Clary,

San Gabriel, Calif.

Application May 26, 1952, Serial No. 290,040

5 Claims. (CI. 94-45) This invention relates to an improved lightweight self-propelled machine for striking oii and leveling freshly poured concrete floors, slabs, and the like, such machines being generally known Such priorproposed screeding machines often included speand provide an improved screeding machine which may readily be Generally speaking,

this invention includes Other objects and advantages of this invention will be readily apparent from the following description of the drawings.

In the drawings:

Fig. l is a top plan view of a screeding machine embodying this invention.

Fig. 2 is a side view of a machine embodying this invention.

Fig. 3 is an end perspective View of the mounting of two of the rollers employed in the machine shown in Fig. 1.

Fig. 4 is a fragmentary end view of the stub shaft mounting of an end of a roller.

An exemplary screeding machine embodying this invention is generally indicated at M and includes end frame means H and i2 and a pluon a concrete slab of a width of twenty feet, the length of roll means It may be approximately twenty-two feet so as to provide about a foot overhang at each end.

The end frame means H and I2 comprise a pair of spaced parallel, longitudinally extending side frame members l5, each side member |5 being of angle section and including a top inboardly directed flange Hi and a depending web H.

The roll means l3 includes a rear driven roller 2|), an intermediate driven roller 2| and a front leveling roller 22 each having lower faces extending below the web |l. Each roller 20, 2| and 22 may be formed ofhollow pipe of suitable diameter, preferably about four to five inches.

The opposite ends of rollers 20, 2| and 22 are each provided with an outwardly extending stub axle 23 which may be fixedly mounted in a pair of axially spaced ported discs 24 and 25. The

latter disc 23 may provide a cover for the open end of the pipe roller. Each stub axle 23 is approximately coaxial with the axis of the associated roller, that is, ample tolerance is permitted and afiords a very slight eccentricity for providin some vibration of the rollers and machine during operation.

The ends of front and rear rollers 22 and are carried by the side members IS in virtually the same manner and for the purposes of brevity, only one of such end mountings will be described. Each stub axle 23 projects outboardly below and beyond the lower edge of depending web H of side member It and extends through a port 28 provided in a vertical leg 29 of an angle bracket 3|]. The angle bracket 30 includes an outwardly extending horizontal leg 3| to which may be suitably secured bearing means 32 axially aligned with the axis of port 23. The bearing means journably receives the outer portion of stub axle 23.

Each angle bracket 30 is adjustably secured to side member is by spaced bolt and nut assemblies 33 extending through Web I1 and through upwardly directed, open-ended spaced slots 34 provided in the upper portion of the vertical le 29. Thus, the support of the front and rear rollers from the side members lii'permits relative adjustment, if desired, between the two rollers with respect to the side members 15 by selective positioning of angle brackets 30 with respect to the nut and bolt assemblies 33. The open-ended slots 3d permit each of these rollers 2i; and 22 to be readily removed from the side members 55 by merely loosening the nut and bolt assemblies 33 and lifting the side members It upwardly so that the bolt assemblies 33 will clear the top open ends of slots 34.

The intermediate roller 2| is journably supported in proximity to front roller 22 by angle brackets 35 carried by side members l5, each angle bracket 3t carrying a bearing means 31 suitably secured to a horizontal, outwardly extending leg 38. The brackets 36 are vertically, movably supported from side members H) by a pair of spaced, vertically extending, closed end slots 353 formed in the vertical leg 40 of each bracket 36, said slots 39 receiving the bolts of bolt and nut assemblies All which extend through the depending web It of each side member. Thus, the intermediate roller 2| is vertically movable and is limited in such vertical movement by the abutment of the ends of slots 39 against the bolts of bolt and nut assemblies 42.

Means to adjustably, vertically position the in- 4 termediate roller 2| so as to either lift the front, leveling roller 22 out of contact with the screed rails, as in normal operation, or to lower the front roller 22 into contact with the screed rails for causing the machine to move backwards may comprise a pair of levers M at each side of the machine. Each lever 44 is pivotally connected at as to an upstanding element is secured in suitable manner to top flange it, generally above stub axle 23 of the intermediate roller 2|. Lever 44 carries at its lower end a wheel 41 which is adapted to bear against and rollingly contact the top edge of an associated bracket 36. The upstanding element 46 carries a stop lug 18 related to the pivotal connection 45 of lever iii so as to position the lever in slightly vertical offset relation when the intermediate roller 2| is urged to its lowermost position by the lever M. The stop lug 43 thus serves to hold or lock the roller in such position. When the intermediate roller 2| is in its lowermost position, the rear roller 26 and the intermediate roller 2| will rollingly contact the screed rails M while the front roller 22 will be spaced slightly above the top edge of the screed rails a distance approximately oneeighth of an inch so as to initially contact and work concrete masses which project upwardly When the lever 44 is in inclined o released position, the intermediate roller 2| is not positively urged against screeds It and the front roller 22 is in contact with the screed rails l4. Since the front roller 22 is driven in opposite rotation from that of the rear roller 20, the front roller may serve to move the machine backwards, as later described.

The rear and intermediate rollers 23 and 2| may be rotatably driven so as to advance the machine along the screeds It. It is understood, of course, that the intermediate roller 2| need not be driven if so desired, and that the rear roller 20 may be the only roller driving the machine forward.

Power means for driving the rear roller 2|] may include a suitable gas-operated motor 56. The motor is supported from end frame means H by a suitable motor mounting plate connected to end frame means H and to which the motor 50 is adapted to be bolted. The drive'shaft of the motor 5G is connected to well-known clutch means 5| for selectively engaging or disengaging the drive shaft. A power transmitting system generally indicated at 52 may include suitably arranged pulley and belt drive means, a reduction gear means 52a, and a sprocket and chain means including a sprocket 53 carried by an extended portion of an adjacent stub axle 23 of the rear roller 28. A clutch means 53a on the output of gear means 52a is operable to engage and disengage the sprocket opposite sprocket 53 for permitting idling of the rear roller 28 and intermediate roller 2|.

At the other end of rear roller 20 the associated stub axle 23 may carry a pulley 54 which may be suitably connected by a belt to a pulley 55 carried by the associated stub axle 23 of the roller 2! for driving the intermediate roller 2|.

Means for driving the front roller 22 in a direction opposite to that of drive rollers 20 and 2| may comprise a second motor means 58 carried by end frame means l2 and located generally opposite to motor means 5|). The motor means 58 has a drive shaft connected through suitable clutch means 59 to a power transmitting system generally indicated at 60 for transmitting power through a pulley and gear arrangement to a pulley til carried by the associated stub shaft 23 at one end of front roller 22.

In operation, it should be noted that the interroller 2t and the intermediate roller 2|. The motor 59' drives the front levelling roller 22 at a selected, relatively high rate of speed as compared with the rear driving roller 2| and is rodirection of is thus in rough form and to screed height. With normal mixes which are not very stiff, usuallyone pass of the screeding machine of this invention over the concrete mix is sufficient to give a, desired rough finish and a slab of concrete of uniform density.

When it is desired to make more than one pass over the freshly poured concrete or to move the machin backwards, the clutch means 53afor motor 50 may be disengaged so that the rollers and 2| may idle. Levers 44 may then be released so as to allow the intermediate roller 2| to return to an uppermost position and thereby lower the front levelling roller into contact with the screed rails. Since the ing in a direction opposite of the screeding machine, driven rearwardly by the. front roller.

If, during operation, there is a tendency of the screeding machine of this invention to weave from one side or the other of the screedrails or to travel at an angle to the desired path of movement of. the machine, the lever 44 on the side of the machine most advanced may be partially released so as to lower the adjacent side of the front levelling roller into contact with screed rail. The opposite rotation of the front levelling roller tends to counteract forward movement of that side of the machine upon contact with the screed The machine may thus be readily operable and controlled by two men either riding on the end frame means or walking alongside each side of the machine.

The screeding machine of. this invention is readily adaptable to slabs of difierent width by removing the rollers from the end frame means and substituting therefor rollers of shorter or different selected length. The disassembly and assembly of the rollers is conveniently accomplished by merely loosening the bolt assemblies front roller is rotatsecurin the angle brackets to the side members. In t e case of the front and rear rollers. the bolts the open-ended slot of such the case of the intermediate removed from engagement slots.

angle brackets. roller, the bolts are with the closed end sembled on similar stub shafts of the selected shorter rollers for example. The angle brackets and associated rollers may then be simply as.- sembled on the side members by reversing the operation described above.

The non-rigidity of the machine and the ample the motors 56 and 59 are in rollerdriving operation so as to efiectively work a freshly poured concrete mix. Increased rotation of the front levelling roller the frequency and amplitude of. the vibrations stiffer character.

It willthus be readily apparent that the screeding machine of this invention is not only lightweight, adjustable to work mixes of dilierent characteristics and adaptable to slabs of diiTercnt widths, but is also self-propelled and may be readily controlled in its advancement as desired. It is also understood that various modifications and changes may be made in the driving means for the rollers, the manner in which the driving means are mounted on the end frame means and the particular structure of the side frame members.

can be readily controlled in its movement by manipulation of levers 44 to advance or retard a selected side of the machine.

All such changes and modifications coming within the scope of the appended claims are embraced thereby.

I claim:

1. A lightweight, adjustable, self-propelled machine for striking off and leveling freshly poured defined between parallel screed a pair of parallel, longitudirear driving roller and an intermediate roller adjacent to the front roller; means supporting said roller means from said side members with the lower faces of the roller means below the side members; said support means for the intermediate roller including angle brackets having slot means therein and bolt means extending through the webs of the side members and the slot means for limited vertical movement of the angle brackets and the intermediate roller; lever means pivotally carried by each side member for pressure contact with the associated angle bracket in one position to move and to hold the intermediate roller in lowermost position for raising the front leveling roller slightly above the plane of the screed rails; each lever means being in non-pressure contact with the angle brackets for the intermediate roller in another position to lower the front roller into contact with screed rails for moving the machine backwards; means mounted intermediate the ends of one side member and operably connected to the rear roller for driving said roller to advance the machine; means intermediate the ends of the other side member and operably connected to the front leveling roller for driving said front roller in a direction opposite to the rear roller and at a speed different than the speed of the rear roller; and means carried by each side member for holding each lever means in pressure contact with the angle bracket associated with the intermediate roller.

2. A lightweight, adjustable, self-propelled machine for striking off and leveling freshly poured concrete panels defined between parallel screed rails, comprising: a pair of parallel, longitudinally extending side members in spaced relation, each of said side members including atop flange and a downwardly extending web; roller means including a front leveling roller, a rear driving roller and an intermediate roller adjacent to the front roller; means supporting said roller means from said side members with the lower faces of the roller means below the side members; said support means for the intermediate roller including angle brackets having slot means therein and bolt means extending through the webs of the side members and the slot means for limited vertical movement of the angle brackets and the intermediate roller; lever means pivotally carried by each side member for pressure contact with the associated angle bracket in one position to move and to hold the intermediate roller in lowermost position for raising the front leveling roller slightly above the plane of the screed rails; each lever means bein in non-pressure contact with the angle brackets for the intermediate roller in another position to lower the front roller into contact with screed rails for moving the machine backwards; means mounted intermediate the ends of one side member and operably connected to the rear roller for driving said roller to advance the machine; means intermediate the ends of the other side member and operably connected to the front leveling roller for driving said front roller in a direction opposite to the rear roller and at a speed different than the speed of the rear roller; each lever means being independently operable for controllably releasing the associated angle bracket for the intermediate roller to lower one side of the front leveling roller to retard advancement of the said one side.

3. In a screeding machine adapted to level freshly poured concrete slabs defined by longitudinally extending screed rails, the combination of: longitudinally extending parallel end frame means; a plurality of rollers including a rear forwardly driven roller, a front rearwardly driven leveling roller, and an intermediate roller; bracket means carried by the end frame means and providing journal mountings for said rollers; the bracket means for the front and rear rollers being in normally fixed relation to the end frame means; the bracket means for the intermediate roller being vertically reciprocally movable with respect to the end frame means for selectively vertically positioning the intermediate roller with respect to the end frame means for lowering the front roller into contact with the screed rails in one position and for lifting the front roller above said rails in another position; lever means pivotally carried by each end frame means for selectively positioning the bracket means for the intermediate roller; said lever means being independently operable to lower one side of the front roller into engagement with the adjacent screed rail for retarding advancement of the same side of the machine; and means carried by the end frame means for selectively driving the rear roller to advance the machine forwardly and for selectively driving the front roller in an opposite direction for moving the machine rearwardly.

4. In a machine as claimed in claim 3 wherein holding means are carried by the end frame means for engagement with the lever means for maintaining the intermediate roller in the said another position.

-5. In a screeding machine for leveling freshly poured concrete slabs defined by spaced apart longitudinally extending screed rails, the combination of: longitudinally extending parallel end frame means; a plurality of transversely arranged rollers, said rollers including a forwardly driven roller, a rearwardly driven leveling roller, and a third roller between said forwardly and rearwardly driven rollers; means carried by the end frame means for mounting said rollers thereon, the mounting means for the forwardly driven roller and rearwardly driven leveling roller being in normally fixed relation to the end frame means; the mounting means for the third roller being adjustable with respect to the frame means for selectively positioning the third roller for lowering the leveling roller into contact with the screed rails in one position and for lifting the leveling roller above said rails in another position; means carried by each end frame means for selectively positioning the mounting means for the third roller for lowering both ends of the third roller and being independently operable to selectively lower either end of the leveling roller into engagement with the adjacent screed rail for retarding advancement of that side of the machine; and means carried by the end frame means for driving the driven roller to advance the machine forwardly and for driving the leveling roller in an opposite direction for moving the machine rearwardly.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,392,161 Hilts Sept. 27, 1921 1,584,385 Lichtenberg May 11, 1926 1,912,976 Fedi June 6, 1933 2,252,188 Krehbiel Aug. 12, 1941 

